Perceived muscular tension, job strain, physical exposure, and associations with neck pain among VDU users; a prospective cohort study

Abstract

Aims: To determine whether perceived muscular tension, job strain, or physical exposure are associated with increased risk of developing neck pain among VDU users. Methods: A baseline questionnaire was answered by 1283 respondents, of whom 671 were free from neck pain at baseline. Perceived muscular tension, job strain, and physical exposure were assessed at baseline. Information about newly developed neck pain was collected in 10 follow up questionnaires and the case definition was the first report of such pain in any of the follow up questionnaires. Median follow up time was 10.9 months. Results: Both men and women who perceived muscular tension at least a few times per week, compared to those who had not perceived muscular tension the preceding month, had an incidence rate ratio (IRR) of 1.9 (95% CI 1.25 to 2.93) for developing neck pain, when stratifying for sex. High perceived muscular tension was associated with an increased risk (IRR 1.6, 95% CI 1.02 to 1.91), even when controlling for job strain, physical exposure, and age in the model stratified by sex. Conclusions: Perceived muscular tension was associated with an increased risk of developing neck pain among VDU users. The combination of high job strain and high perceived muscular tension was associated with higher risk of developing neck pain than the combination of high physical exposure and high perceived muscular tension. There was an indication of an excess risk due to interaction between high physical exposure and high job strain. N eck pain is believed to have a multifactorial aetiology, with physical, psychosocial and individual factors interacting in the development of these disorders, [1][2][3][4][5][6][7] though some investigators conclude that psychosocial factors are of greater importance than physical.8 9 Several theoretical models of how these factors relate to each other and their associations with musculoskeletal pain have been proposed. [10][11][12][13][14] There are no generally accepted criteria for classification of pain in the neck/shoulder region, but the umbrella term cervicobrachial disorders has been used. 15 In previous cross-sectional studies, we found that both physical and psychosocial factors were associated with muscle activity, measured with electromyography (EMG). [16][17][18][19] We have also found positive associations between perceived muscular tension and muscle activity assessed with EMG. 18Theorell and colleagues 20 reported that perceived muscular tension was associated with symptoms from the back, neck, and shoulders in a cross-sectional study. Crosssectional studies of populations characterised by low biomechanical exposure-that is, customer service work, have observed associations between perceived general tension and musculoskeletal symptoms in the neck/shoulder region. 22Whether perceived muscular tension is a risk factor or an intermediate in the development of musculoskeletal symptoms is unknown, though Holte and colleagues 23 suggested perceived general tension to be an intermediate response to organisat...

Individual, physical and psychological risk factors for neck pain in Australian office workers: a 1-year longitudinal study

“…It is possible that this may be due to limited statistical power resulting from the small sample size in this study, although the 95% CI is narrow. Psychosocial work factors such as high job demands, low decision latitude and co-worker support, have frequently been found to be associated with increased risk of neck pain in office workers [17,19,21,27,38] as well as in some [3,30] but not all [24] studies of general working populations.…”

“…gender) [6,11,19,21] work environment factors (e.g. repetitive work, exposure level) [19,21,38] and psychosocial factors (e.g. stress, high job demands, low decision latitude) [4,6,17,21,38].…”

“…repetitive work, exposure level) [19,21,38] and psychosocial factors (e.g. stress, high job demands, low decision latitude) [4,6,17,21,38]. However, methodological considerations limit interpretation of existing studies either because of high loss to follow-up (22% [21] to 48% [38]) in longitudinal studies, which can introduce significant bias into the study findings, or because a cross-sectional design was used [6,8,11,17,19], where inferences of cause-and-effect cannot be made.…”

Concordance between VDU-users’ ratings of comfort and perceived exertion with experts’ observations of workplace layout and working postures

“…However, some studies have shown an association between the perception of general muscular tensio symptoms in the neck and shoulder area (Holte et al, 2003;Westgaard and De Luca, 2001). Another longitudinal study of muscle tension in the neck and shoulder area and the incidence of neck symptoms showed that high perceived muscle tension was a risk factor for the development of neck symptoms among computer users (Wahlstrom et al, 2004).…”

“…For instance, it has been suggested that perceived muscle tension is associated with neck and upper extremity symptoms/disorders (Wahlstrom et al, 2004). These perceived sensations may regarded as responses to biomechanical strain (e.g.…”